1. Field of the Invention
The present invention relates to a sealed enclosure provided with a valve at least part of which extends inside the enclosure and is formed between two flexible sheets connected along two non-converging lines to form therebetween a duct upon spacing apart said flexible sheets from one another to allow the passage of a fluid between the inside and the outside of the enclosure, said sheets being arranged to be applied against one another upon ceasing of the application thereto of a force tending to hold them apart, thus preventing said fluid from leaving the enclosure. This invention also relates to a method of manufacturing this enclosure as well as a method of packaging a beverage.
2. Description of the Prior Art
Sealed enclosures of this type have already been proposed, provided with a valve which is in extension of the enclosure""s wall, thereby avoiding problems relating to securing a fitted-on valve. Such enclosures are described notably in GB 826,784 and FR 1 338 549. The latter document proposes to make the enclosure out of a tubular element. This solution has the drawback of necessitating folding over the tubular element in order to place the valve inside the enclosure. This solution does not lend itself to be manufactured using automated mass-production lines that generally include folding, welding and cutting stations.
As for GB 826,784, its principal drawback resides in the fact that, in case the enclosure is used for packaging a beverage, the beverage must be introduced via the valve""s orifice which necessarily is of small section because it is designed for the passage of a drinking straw. Because of this, the speed of filling the enclosure is necessarily reduced due to the small section of the passage, which limits the speed of the production line. Such a solution is evidently not economically viable.
Another drawback is that this enclosure is not adapted to be produced using machinery which is known, available or adaptable to the production thereof.
The aim of the present invention is to at least partly remedy the above-mentioned drawbacks.
This invention concerns a sealed enclosure of the above-mentioned type. It also concerns a method of packaging a beverage in this sealed enclosure. Lastly, it concerns a method of manufacturing the sealed enclosure.
An advantage of the proposed solution is to enable the sealed enclosure to be manufactured with its valve integrated in a single wall of the enclosure, which enables use of existing production lines starting with a flat plastic film. When the enclosure is for packaging beverages, the enclosure can be filled at a high rate via an orifice which is of much greater section than the valve.